Hollow sheet-metal structure



PuEy 3, 1923., EAWLTZ c. DORNIER HOLLOW SHEET METAL STRUCT URE Filed June 28. 1920 -2 Sheets-Sheet INVENTOR Juiy 3, 1923. 1,460,372

c. DQRNIER {IOLLOW SHEET METAL STRUCTURE Filed'June 28, 1920 2 Sheets-Shet 2 2. e v J 1m M \a INVENTURI Pmented duly 3, i923.

hurrah stares CLAUDIUS DORNIER, 0F FRIEDRICHSHAFEN, GERMANY, ASSIGNOR 0F ONE-HALF T0 DOJRNIER-METALLBAUTEN, GESE-LLSCHAFT MIT BESCRANKTER HAFTUNG, 0F

FRIEDRICHSHAFIEN, GERMANY.

HOLLOW SHEET-METAL STRUCTURE.

Application filed June 28, 1920. Serial No. 392,541.

To all whom it may concern:

Be it known that I, CLAUDIUS DonNIER, a citizen of the German Empire, residing at Friedrichshafen, Germany, have invented certain new and useful Improvements in Hollow Sheet-Metal Structures '(for which I have filed applications in Germany May l, 1917, and Nov. 10, 1917), of whichthe following is a specification.

My invention relates to hollow bodies in the case of which, as for example, in that of the bulls of flying machines, it is desired to combine lightness of weight with great stability, and where, moreover, the inside space is to be made as large as possible. It rclates more especially to the construction and fitting together of the entire body out of a plurality of simple members.

Theknown forms of construction of the kind described consist of a reinforcing or stifiening frame composed of longitudinal ribs or stay rings, said frame being subsequently enveloped with a cover providing the outer form. For the purpose of safeguardin the stability of the frame, the several fiel s and the stay rings, serving inter alia for the connection of sheet metal sections, are in addition often reinforced by trusses or tension wires.

A structure of this type involves serious drawbacks. The construction of the frame, as also, it may be, the stiffening thereof, requires considerable time. Besides a great deal of building material. of various kind is needed for the purpose. special reinforcements or stays necessitated, the available clear space is considerably reduced. The covering subsequently added causes a decided increase in weight.

My present invention aims to obviate these drawbacks which are especially prominent when constructing large-sized hollow bodies, and to reduce the time required for construe tion, the weight of the structure when ready, the number of the members used, and consequently the costs, while at the same time increasing the stability of the outer structure as well as the available inside space, and lastly to render the several sections of the total structure more uniform.

This object is attained by the outer skin being made use of to the like extent as the Owing to the frame-shaped members for. staying or stiffenlng purposes, whereby the construction of special rigid frame work having good bearmg capacity even though not covered, is rendered unnecessary.

In accordance with the foregoing explanations, the subject matter of this invention substantally forms a hollow structure, provided with frame-like trusses or stays, and especially adapted to constitute the hull or body of a flying machine, in the case of which a group of frames, conjointly with a strong sheet iron cover or mantle serving as a common flange, are united'to a homogenous structure. Owing to the fact that the flanges of the frames, united in the manner aforementioned, are disposed in the sheet iron mantle, i. e. in one single body, every danger of any of the individual frames proper to the system being shifted out of position is excluded. When employing frames having the customary cross-section, these may be in de less strong than those hitherto used. *urther, according to my invention, so-called open or channelled section forms, having a slight thickness of' wall may be employed as frame members, said open section forms excelling by lightness of weight and ease of manufacture. For by reason of their connection to the sheet iron mantle, which for its part serves as a common flange member, these said open sections are united to form a comin consequence, possess a specially good resisting capacity.

If the hollow body, say, for example, the hull of a flying machine, be of such a length that the sheet iron mantle cannot be made all in one piece, then, in accordance with a modified formof my improved structure, the edge sections are continued right along, a plurality of sheet metal sections being fixed thereon, each of these being provided at its ends with annularly recessed supporting plates of such shape that always two adjacent supporting plates constitute, together with the mantle sections common to all an annular body of essentially enclosed cross-section.

A specially favourable structure of these siniiporting plates or section rims in two 'plete system of closed hollow sections, which,

parts which, as such may also be employed in the middle of a section, will be obtained on each single rim being so shaped that when stretched or extended, it possesses a U-like section having a comparatively broad web portion, and diagonal, outwardly directed, but for the rest rectangularly I flanges. The abutting flanges of each double rim may then extend farther in a radial sense, than would be possible in the case of a single-part groove-shaped ring having a radial flange disposed in the symmetrical plane of the groove.

The uninterrupted intersecting of longitudinal and transverse frames, having supporting capacity, can however also be obtained in accordance with my invention by arranging the longitudinal frame sections, open per se, on the one side, and the transverse frame sections on the opposite side of the skin common to both, and in addition connecting them to said skin. The advantage of this construction over the one described aboveresides in the fact that the skin may be comparatively thin, and that likewise smaller sections may be chosen for the hollow rods, as the entire structure is stayed or stiffened in two directions in a completely uniform manner. Moreover by these means the weight is considerably lessened. But besides this intricate forms of cov ers possessing great supporting capacity may be obtained with ease, as the rod sections, which are comparatively weak, may be readily bent to any shape desired before being united with the outer skin to a rigid structure. v

Different forms of construction embodying the subject matter of my invention are illustrated in the accompanying drawings forming a part of this specification. In the drawings- Fig. 1 is a longitudinal section of the hull of a flying machine, and

Fi 2 a cross-section (on an enlarged scalefl according to line 2-2 in Fig. 1.

Fig. 3 is a. side elevation of a modified form, partly in longitudinal section,

Fig. 4 a cross-section along the line 22 in Fig. 3,

Fig. 5 a cross-section of a supporting surface along line 3-3 in. Fig. 6,

Fig.6 a vertical longitudinal section of said surface, and

Figs. 7 and 8 similar views of a modified form of supporting surface.

The principal form of the hull illustrated in Figs. 1 and 2 approximately resembles a four-sided pyramid. Ihe cover is formed by a sheet metal mantle A, the cross-section of which is represented by a square having slightly outwardly bulged sides a and flattened corners a In the interior of the mantle there are disposed along the edges and corresponding directed to the corners a open section rods B, the flanges b of which abut against the mantle surface, being connected to this latter, say, for example, by rivets and thus forming hollow longitudinal sections.

At certain intervals, and this at right angles to the longitudinal axis of the hull, there aredisposed annularly recessed supporting plates C and D. The plates C are disposed in pairs one beside the other. When stretched they form a U-shaped section having a comparatively broad web and diagonal outwardly directed flanges a and 0 which for the rest are placed the one above the other at right angles. When built in, theyabut with flanges 0 against the periphery a of the. sheet metal mantle, while the inwardly directed flanges a of two adjacently disposed sheet iron plates come'to abut against each other. By thus riveting on the flanges 0 there is created a rim section having a channel-shaped crosssection. As soon as the rim has been joined to the mantle, say for example, by riveting, it constitutes together with this latter a hollow annular section. The plates D which are always arranged between two sheet iron plates C, are stayedor stiffened by grooves d while at their edge they are provided with flanges d, by which they may be also fixed to the sheet iron mantle in order to assist in reinforcing or staying the same.

In the place of the two-part supporting I plates C, there may be employed from the very outset open sections all in one piece, having flanges disposed along a single plane, since these may also be readily connected-and as will be clearly understood from the foregoing-with the sheet metal mantle to form closed hollow cross-sections of great stability. However, the said supporting plates C made in two parts will be found especially advantageous when employed as end-plates in connection with single mantle sections, since these may then be far more easily united to form a complete structure possessing great resisting capacity. 1

The longitudinal and transverse ribs may, if desired, be connected at the points of in tersection. However, a reinforcement of this kind is not absolutely necessary, in contradistinction to the known constructions, as the sheet iron mantle forms the common flange-and thus effectively prevents any mutual displacement of the longitudinal and transverse ribs.

In the hull or body disclosed by I igs. 3 and 4, the skin A is connected by rivets on 'the inside to annular cross-frames l3 and on "the outside to longitudinal frames or rods 0.

each other to the like degree. As may established by means of riveting, this being the measure most frequently resorted to in practice. However, the connection between the members may also be effected in any other manner desired, say, for instance, by soldering, welding or by screws. For the only important point for the structure when ready is that thesingle members A, B and C, which, individually considered, possess but little supporting capacity, shall by being joined, form an integral structure capable of offering good resistance and possessing enclosed hollow outer and inner rib portions which -will stiffen out conjointly with the common outer skin and mutually amorgg e observed from Fig. 3, all the longitudinal frame members C need not be continued along the entire length of the hull or body. For, particularly in the case of the intermediate rods, it will be perfectly sufficient if they are merely provided at the points subject to an increased strain.

In the supporting surface according, to Figs. 5 and 6, a number of open or channeled rods D, arranged in the direction of the spars or beams generally employechare fitted closely to the inside face of a skin E. Similar bars or rods F, extending substantially at right angles to said spars are fixed to the outside of said skin E. By the connection with the skin there is created a perfectly strong system of transverse frames F1 and longitudinal frames D, the result being that the supporting surface thus constructed will support itself without the aid of special cross-beams. In .the case of very great breadth of wing, the superposed longitudinal frames D may, of course, be still further stayed by means of a frame work G.

The supporting surface according to Figs. 7 and 8, essentially differs from the one justdescribed b the fact of the longitudinal rods H being 10 ged on the outside, and the transverse frames J on the inside of their common skin K. The frame work L, shown in Fig. 7, is not required as a rule, though, of course, if the surface be very broad, it will materially increase its rigidity.

The manner of fixing the flanges may also be effected in any other known manner than by riveting, nor is it at all necessary to employ the same kind of metallic building materials for the construction of the entire body.

I claim.

1. In a hollow metallic structure in combination, a sheet metal mantle and a plurality of longitudinal trusses formed of open channelled rods connected with said mantle to nelled rods and cross-frames of substantially angular section connected with said mantle to form a plurality of coherent closed hollow sections.

' 3. In a hollow metallic structure in combination, a sheet metal mantle and a plurality of longitudinal trusses formed of open channelled rods and annular cross-frames of substantially angular section connected with said mantle to form a plurality of coherent closed hollow sections.

4. In a hollow metallic structure in combination a plurality of sections, each section consisting of a sheet metal mantle and cross-frames of substantially angular sec: tion connected with said mantle to form an annular body and a plurality of longitudinal trusses formed of open channelled rods extending each through several sections and serving to connect them;

5. In a hollow metallic structure in combination, a sheet metal mantle and a plurality of longitudinal trusses formed of open channelled rods and cross-frames U-section connected with said mantle to form a plurality of coherent closed hollow sections.

6. In a hollow metallic structure in combination, a sheet metal mantle and a plurality of longitudinal trusses formed of open channelled rods and annular cross-frames of substantially U-sections connected wit-h said mantle to form a plurality of coherent closed hollow sections.

7. In a hollow metallic structure in combination, a sheet metal mantle and a plurality of longitudinal trusses formed of open channelled rods and annular cross-frames, each formed oftwo juxtaposed rings of U-section, connected with said mantle to form aplurality of coherent closed sections.

8. In a hollow metallic structure in combination, a sheet metal skin and longitudinal rods and cross-frames of substantially groove-shaped section extending in intersect- 13g planes-and fixed to opposite faces of said s in.

9. In a flying machine in combination. a sheet metal skin and longitudinal rods and cross-frames of substantially groove-shaped section extending in intersecting planes, said rods being fixed to the outer and said crossframes to the inner surface of said skin.'

In testimony whereof I affix in Si nature.v

CLAUDIUS D Ri IER.

of substantially 

